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Issued at 300 AM CST Fri Jun 13 2025 ZCZC MIATCPEP4 ALL TTAA00 KNHC DDHHMM BULLETIN Potential Tropical Cyclone Four-E Advisory Number 3 NWS National Hurricane Center Miami FL EP042025 300 AM CST Fri Jun 13 2025 ...DISTURBANCE EXPECTED TO BECOME A TROPICAL STORM LATER TODAY... ...TROPICAL STORM WATCH REMAINS IN EFFECT FOR THE COAST OF SOUTHWESTERN MEXICO... SUMMARY OF 300 AM CST...0900 UTC...INFORMATION ---------------------------------------------- LOCATION...12.8N 100.8W ABOUT 340 MI...550 KM S OF ZIHUATANEJO MEXICO MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H PRESENT MOVEMENT...NNW OR 335 DEGREES AT 9 MPH...15 KM/H MINIMUM CENTRAL PRESSURE...1006 MB...29.71 INCHES WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY: None. SUMMARY OF WATCHES AND WARNINGS IN EFFECT: A Tropical Storm Watch is in effect for... * Tecpan De Galeana to Manzanillo A Tropical Storm Watch means that tropical storm conditions are possible within the watch area, generally within 48 hours. A Tropical Storm Warning may be required for portions of the watch area later today. For storm information specific to your area, please monitor products issued by your national meteorological service. DISCUSSION AND OUTLOOK ---------------------- At 300 AM CST (0900 UTC), the disturbance was centered near latitude 12.8 North, longitude 100.8 West. The system is moving toward the north-northwest near 9 mph (15 km/h). A turn toward the northwest is expected later today, with a turn toward the west-northwest forecast by Sunday. On the forecast track, the disturbance is forecast to move parallel to, but offshore of, the southwestern coast of Mexico. Maximum sustained winds are near 35 mph (55 km/h) with higher gusts. Strengthening is expected during the next couple of days. The system is forecast to become a tropical storm later today and continue strengthening on Saturday as it moves parallel to the coast of southwestern Mexico. * Formation chance through 48 hours...high...90 percent. * Formation chance through 7 days...high...90 percent. The estimated minimum central pressure is 1006 mb (29.71 inches). HAZARDS AFFECTING LAND ---------------------- Key messages for Potential Tropical Cyclone Four-E can be found in the Tropical Cyclone Discussion under AWIPS header MIATCDEP4 and WMO header WTPZ44 KNHC. RAINFALL: Rainfall totals of 2 to 4 inches, with localized amounts up to 6 inches, are possible across portions of the Mexican states of Guerrero, Michoacán, and Colima through this weekend. This rainfall may lead to areas of flooding and mudslides. For a complete depiction of forecast rainfall associated with Potential Tropical Cyclone Four-E, please see the National Weather Service Storm Total Rainfall Graphic available at hurricanes.gov/graphics_ep4.shtml?rainqpf WIND: Tropical storm conditions are possible within the watch area on Saturday. SURF: Swells generated by Potential Tropical Cyclone Four-E will affect portions of the coast of southwestern Mexico during the next few days. These swells are likely to cause life-threatening surf and rip current conditions. Please consult products from your local weather office. NEXT ADVISORY ------------- Next intermediate advisory at 600 AM CST. Next complete advisory at 900 AM CST. $$ Forecaster Beven NNNN

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0228 AM CDT Fri Jun 13 2025 Valid 151200Z - 161200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTHEAST MONTANA...THE DAKOTAS AND NORTHERN NEBRASKA... ...SUMMARY... Scattered severe storms, capable of isolated large hail and severe wind gusts, are expected on Sunday from parts of southeast Montana southeastward into northern Nebraska. Elsewhere in the Great Plains, marginally severe storms will be possible. A few severe wind gusts may also occur from parts of North Carolina into southern Virginia. ...Northern Plains/Northern Nebraska... A mid-level ridge is forecast to remain over the central and northern High Plains on Sunday, as a subtle shortwave trough rides up and over the ridge. At the surface, a low is forecast to develop over Wyoming, with upslope flow remaining over much of the northern Plains. A moist airmass will be located from eastern Montana into the Dakotas and Nebraska, where moderate to strong instability is forecast to develop by afternoon. As surface temperatures warm during the day, convective initiation is expected in the higher terrain of the northern High Plains, with additional storms possible further east into parts of the Dakotas. NAM forecast soundings late Sunday afternoon near the instability axis have MLCAPE peaking near 4000 J/kg with 700-500 mb lapse rates near 8 C/km. 0-6 km shear is forecast to be in the 30 to 40 knot range. This environment should support supercell development, with large hail and wind damage being possible. A tornado could also occur. The severe threat will likely persist into the evening, as low-level flow gradually increases across the region. ...Southern Nebraska/Kansas/Oklahoma/North Texas... A moist airmass will remain in place across much of the southern and central Plains on Sunday. Surface dewpoints from the upper 60s to the mid 70s F will contribute to the development of strong instability across parts of this airmass by afternoon. In spite of a lack of large-scale ascent, isolated convective initiation will be possible as surface temperatures peak in the afternoon. The most likely location for storm development would be along or near any residual outflow boundary. Forecast MLCAPE in the 2500 to 3500 J/kg range, along with steep low to mid-level lapse rates, and moderate deep-layer shear would support an isolated severe threat. Hail and marginally severe wind gusts would be the primary threats. ...North Carolina/Southern Virginia... A mid-level shortwave trough is forecast to move eastward across the southern and central Appalachians on Sunday. Ahead of the trough, a moist airmass is forecast over parts of the Carolinas and Virginia. As surface temperatures warm in the late morning and early afternoon, convective initiation is expected in the higher terrain of the southern and central Appalachians. As this convection moves eastward into the lower elevations, thunderstorms are expected to form. Although deep-layer shear is forecast to remain relatively weak, moderate instability and steep low-level lapse rates could be sufficient for isolated severe wind gusts. ..Broyles.. 06/13/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0228 AM CDT Fri Jun 13 2025 Valid 151200Z - 161200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTHEAST MONTANA...THE DAKOTAS AND NORTHERN NEBRASKA... ...SUMMARY... Scattered severe storms, capable of isolated large hail and severe wind gusts, are expected on Sunday from parts of southeast Montana southeastward into northern Nebraska. Elsewhere in the Great Plains, marginally severe storms will be possible. A few severe wind gusts may also occur from parts of North Carolina into southern Virginia. ...Northern Plains/Northern Nebraska... A mid-level ridge is forecast to remain over the central and northern High Plains on Sunday, as a subtle shortwave trough rides up and over the ridge. At the surface, a low is forecast to develop over Wyoming, with upslope flow remaining over much of the northern Plains. A moist airmass will be located from eastern Montana into the Dakotas and Nebraska, where moderate to strong instability is forecast to develop by afternoon. As surface temperatures warm during the day, convective initiation is expected in the higher terrain of the northern High Plains, with additional storms possible further east into parts of the Dakotas. NAM forecast soundings late Sunday afternoon near the instability axis have MLCAPE peaking near 4000 J/kg with 700-500 mb lapse rates near 8 C/km. 0-6 km shear is forecast to be in the 30 to 40 knot range. This environment should support supercell development, with large hail and wind damage being possible. A tornado could also occur. The severe threat will likely persist into the evening, as low-level flow gradually increases across the region. ...Southern Nebraska/Kansas/Oklahoma/North Texas... A moist airmass will remain in place across much of the southern and central Plains on Sunday. Surface dewpoints from the upper 60s to the mid 70s F will contribute to the development of strong instability across parts of this airmass by afternoon. In spite of a lack of large-scale ascent, isolated convective initiation will be possible as surface temperatures peak in the afternoon. The most likely location for storm development would be along or near any residual outflow boundary. Forecast MLCAPE in the 2500 to 3500 J/kg range, along with steep low to mid-level lapse rates, and moderate deep-layer shear would support an isolated severe threat. Hail and marginally severe wind gusts would be the primary threats. ...North Carolina/Southern Virginia... A mid-level shortwave trough is forecast to move eastward across the southern and central Appalachians on Sunday. Ahead of the trough, a moist airmass is forecast over parts of the Carolinas and Virginia. As surface temperatures warm in the late morning and early afternoon, convective initiation is expected in the higher terrain of the southern and central Appalachians. As this convection moves eastward into the lower elevations, thunderstorms are expected to form. Although deep-layer shear is forecast to remain relatively weak, moderate instability and steep low-level lapse rates could be sufficient for isolated severe wind gusts. ..Broyles.. 06/13/2025 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0212 AM CDT Fri Jun 13 2025 Valid 141200Z - 151200Z ...Synopsis... A modestly strong mid-level jet is expected to be situated over the northwestern CONUS during the day on Saturday, and strong surface heating in this area is expected to mix down some of that momentum from aloft. Given gusts of 20-25 mph expected along with 10-15% RH and dry fuels, have introduced an Elevated area in northwest Nevada. Additionally, modestly dry fuels across portions of the Columbia River Valley in Washington and Oregon along with 15-20% RH along with gusts of 20-25 mph warrant the introduction of an Elevated area here, as well. ..Supinie.. 06/13/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0212 AM CDT Fri Jun 13 2025 Valid 141200Z - 151200Z ...Synopsis... A modestly strong mid-level jet is expected to be situated over the northwestern CONUS during the day on Saturday, and strong surface heating in this area is expected to mix down some of that momentum from aloft. Given gusts of 20-25 mph expected along with 10-15% RH and dry fuels, have introduced an Elevated area in northwest Nevada. Additionally, modestly dry fuels across portions of the Columbia River Valley in Washington and Oregon along with 15-20% RH along with gusts of 20-25 mph warrant the introduction of an Elevated area here, as well. ..Supinie.. 06/13/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0212 AM CDT Fri Jun 13 2025 Valid 131200Z - 141200Z ...CRITICAL FIRE WEATHER AREA FOR PARTS OF NORTHWESTERN NEVADA... ...Synopsis... A belt of southwesterly flow aloft with an embedded shortwave trough will be situated over the northwestern CONUS during the day. This will provide the focus for fire weather concerns, with the strong flow aloft mixing down due to strong surface heating, producing gusts of 25-30 mph across parts of northwestern Nevada. This will occur in the presence of 10-15% RH for several hours. Fuels in this area are fairly dry, so have maintained the Critical area across parts of northwestern Nevada. Similarly, modestly dry fuels along with gusty winds and 15-20% RH will result in Elevated fire conditions across portions of the Columbia Valley in Washington and Oregon. ..Supinie.. 06/13/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0212 AM CDT Fri Jun 13 2025 Valid 131200Z - 141200Z ...CRITICAL FIRE WEATHER AREA FOR PARTS OF NORTHWESTERN NEVADA... ...Synopsis... A belt of southwesterly flow aloft with an embedded shortwave trough will be situated over the northwestern CONUS during the day. This will provide the focus for fire weather concerns, with the strong flow aloft mixing down due to strong surface heating, producing gusts of 25-30 mph across parts of northwestern Nevada. This will occur in the presence of 10-15% RH for several hours. Fuels in this area are fairly dry, so have maintained the Critical area across parts of northwestern Nevada. Similarly, modestly dry fuels along with gusty winds and 15-20% RH will result in Elevated fire conditions across portions of the Columbia Valley in Washington and Oregon. ..Supinie.. 06/13/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1258 AM CDT Fri Jun 13 2025 Valid 141200Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL AND NORTHERN HIGH PLAINS... ...SUMMARY... Scattered severe storms capable of large hail and isolated damaging wind gusts will be possible across parts of the central and northern High Plains Saturday afternoon and evening. Marginally severe storms will also be possible in parts of southern and central Plains. ...Central and Northern High Plains... A mid-level ridge will move eastward across the north-central U.S. on Saturday. In the wake of the ridge, a subtle shortwave trough will move into the central and northern High Plains. At the surface, a moist airmass will be present across much of the Great Plains. Upslope flow will be in place over the central and northern High Plains, where a pocket of moderate to strong instability is forecast to develop Saturday afternoon. As surface temperatures warm during the day, convection will first initiate in the higher terrain from east-central Montana southeastward to the Black Hills. From this convection, scattered thunderstorms are expected to develop and move eastward into the lower elevations of the central and northern High Plains. An impressive thermodynamic environment is forecast to be in place by Saturday afternoon from northeast Wyoming into western Nebraska, where model forecasts suggest MLCAPE could peak around 4000 J/kg. Near the instability maximum, 700-500 mb lapse rates are forecast to be near 8 C/km. In spite of this, forecast soundings in the central and northern High Plains have a capping inversion in place during the afternoon. This should keep the initial convective development confined to the higher terrain of southeast Montana, northeast Wyoming and southwestern South Dakota. Forecasts soundings late Saturday afternoon in this area mostly have 0-6 km shear in the 30 to 40 knot range, mainly due to mid-level speed shear. The shear, combined with the moderate to strong instability, will likely support a severe threat. Supercells should be capable of isolated large hail and severe wind gusts. The threat is expected to persist into the mid to late evening, as low-level flow increases. ...Southern and Central Plains... A mid-level ridge will move eastward across the Great Plains on Saturday. At the surface, a moist airmass will be located across much of the southern and central Plains. As surface temperatures warm during the day, moderate instability is forecast to develop throughout much of this airmass. Due to the presence of the ridge, large-scale ascent will remain weak in most areas. In spite of this, isolated thunderstorms may still develop in areas where low-level convergence and surface heating are maximized, and further west in the higher terrain of the central and southern High Plains. Forecast soundings late Saturday afternoon across the southern and central Plains generally have large surface-temperature dewpoint spreads with steep lapse rates. This environment will also have sufficient deep-layer shear for isolated severe storms. Hail and marginally severe wind gusts are expected to be the primary threats. ..Broyles.. 06/13/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1258 AM CDT Fri Jun 13 2025 Valid 141200Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL AND NORTHERN HIGH PLAINS... ...SUMMARY... Scattered severe storms capable of large hail and isolated damaging wind gusts will be possible across parts of the central and northern High Plains Saturday afternoon and evening. Marginally severe storms will also be possible in parts of southern and central Plains. ...Central and Northern High Plains... A mid-level ridge will move eastward across the north-central U.S. on Saturday. In the wake of the ridge, a subtle shortwave trough will move into the central and northern High Plains. At the surface, a moist airmass will be present across much of the Great Plains. Upslope flow will be in place over the central and northern High Plains, where a pocket of moderate to strong instability is forecast to develop Saturday afternoon. As surface temperatures warm during the day, convection will first initiate in the higher terrain from east-central Montana southeastward to the Black Hills. From this convection, scattered thunderstorms are expected to develop and move eastward into the lower elevations of the central and northern High Plains. An impressive thermodynamic environment is forecast to be in place by Saturday afternoon from northeast Wyoming into western Nebraska, where model forecasts suggest MLCAPE could peak around 4000 J/kg. Near the instability maximum, 700-500 mb lapse rates are forecast to be near 8 C/km. In spite of this, forecast soundings in the central and northern High Plains have a capping inversion in place during the afternoon. This should keep the initial convective development confined to the higher terrain of southeast Montana, northeast Wyoming and southwestern South Dakota. Forecasts soundings late Saturday afternoon in this area mostly have 0-6 km shear in the 30 to 40 knot range, mainly due to mid-level speed shear. The shear, combined with the moderate to strong instability, will likely support a severe threat. Supercells should be capable of isolated large hail and severe wind gusts. The threat is expected to persist into the mid to late evening, as low-level flow increases. ...Southern and Central Plains... A mid-level ridge will move eastward across the Great Plains on Saturday. At the surface, a moist airmass will be located across much of the southern and central Plains. As surface temperatures warm during the day, moderate instability is forecast to develop throughout much of this airmass. Due to the presence of the ridge, large-scale ascent will remain weak in most areas. In spite of this, isolated thunderstorms may still develop in areas where low-level convergence and surface heating are maximized, and further west in the higher terrain of the central and southern High Plains. Forecast soundings late Saturday afternoon across the southern and central Plains generally have large surface-temperature dewpoint spreads with steep lapse rates. This environment will also have sufficient deep-layer shear for isolated severe storms. Hail and marginally severe wind gusts are expected to be the primary threats. ..Broyles.. 06/13/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1237 AM CDT Fri Jun 13 2025 Valid 131200Z - 141200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF MONTANA... ...SUMMARY... Scattered severe thunderstorms are expected across much of Montana, extending south across the central High Plains. The greatest concentration of severe is expected across Montana where very large hail, and severe winds are anticipated. ...Montana, south into the central High Plains... 500mb speed max (50+kt) is forecast to translate across southern OR into the northern Rockies by late afternoon as a short-wave trough advances inland. At the surface, southeasterly low-level flow is expected to be maintained across much of MT east of the higher terrain, and moist boundary-layer conditions will be drawn deep into the mountains prior to convective initiation. Early this morning, lower-mid 50s surface dew points were observed as far west as Helena and Polson. Latest model guidance suggests CINH will be negligible by 18z across the higher terrain, and convection should readily develop within an increasingly sheared and modestly buoyant environment. NAM sounding for C18 at 18z exhibits 65kt 0-6km bulk shear, with 8 C/km lapse rates, and 1300 J/kg SBCAPE. Hodographs favor very large hail with these conditions and 2+ inch stones are certainly possible with the more robust supercells. Scattered supercells should develop by early afternoon then spread east and mature as they advance toward central/southern MT. Some tornado threat can be expected with these storms as ample low-level shear should be present. With time multiple thunderstorm clusters could emerge and severe winds may become more common as this activity propagates toward southern MT. Farther south across the High Plains of eastern WY into western KS, more isolated activity is expected within a weaker flow regime. 00z model guidance suggests a surface boundary will be draped across this region, extending southeast into central OK. This boundary will likely serve as the focus for diurnally enhanced convection. Forecast soundings suggest strong SBCAPE will be noted across the central High Plains into central OK where values should exceed 3000-4000 J/kg at lower latitudes. Somewhat stronger northwesterly flow will extend across eastern OK into western AR and this may result in some organizational potential along the backside of the MS Valley trough. Have extended severe probs across OK into western AR to account for this possibility. ..Darrow/Supinie.. 06/13/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1237 AM CDT Fri Jun 13 2025 Valid 131200Z - 141200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF MONTANA... ...SUMMARY... Scattered severe thunderstorms are expected across much of Montana, extending south across the central High Plains. The greatest concentration of severe is expected across Montana where very large hail, and severe winds are anticipated. ...Montana, south into the central High Plains... 500mb speed max (50+kt) is forecast to translate across southern OR into the northern Rockies by late afternoon as a short-wave trough advances inland. At the surface, southeasterly low-level flow is expected to be maintained across much of MT east of the higher terrain, and moist boundary-layer conditions will be drawn deep into the mountains prior to convective initiation. Early this morning, lower-mid 50s surface dew points were observed as far west as Helena and Polson. Latest model guidance suggests CINH will be negligible by 18z across the higher terrain, and convection should readily develop within an increasingly sheared and modestly buoyant environment. NAM sounding for C18 at 18z exhibits 65kt 0-6km bulk shear, with 8 C/km lapse rates, and 1300 J/kg SBCAPE. Hodographs favor very large hail with these conditions and 2+ inch stones are certainly possible with the more robust supercells. Scattered supercells should develop by early afternoon then spread east and mature as they advance toward central/southern MT. Some tornado threat can be expected with these storms as ample low-level shear should be present. With time multiple thunderstorm clusters could emerge and severe winds may become more common as this activity propagates toward southern MT. Farther south across the High Plains of eastern WY into western KS, more isolated activity is expected within a weaker flow regime. 00z model guidance suggests a surface boundary will be draped across this region, extending southeast into central OK. This boundary will likely serve as the focus for diurnally enhanced convection. Forecast soundings suggest strong SBCAPE will be noted across the central High Plains into central OK where values should exceed 3000-4000 J/kg at lower latitudes. Somewhat stronger northwesterly flow will extend across eastern OK into western AR and this may result in some organizational potential along the backside of the MS Valley trough. Have extended severe probs across OK into western AR to account for this possibility. ..Darrow/Supinie.. 06/13/2025 Read more

5-Day Uncertainty Track last updated Fri, 13 Jun 2025 05:34:33 GMT


Wind Speed Probabilities last updated Fri, 13 Jun 2025 03:21:36 GMT

Issued at 1200 AM CST Fri Jun 13 2025 727 WTPZ34 KNHC 130531 TCPEP4 BULLETIN Potential Tropical Cyclone Four-E Intermediate Advisory Number 2A NWS National Hurricane Center Miami FL EP042025 1200 AM CST Fri Jun 13 2025 ...DISTURBANCE GRADUALLY BECOMING BETTER ORGANIZED... ...TROPICAL STORM WATCH IN EFFECT FOR THE COAST OF SOUTHWESTERN MEXICO... SUMMARY OF 1200 AM CST...0600 UTC...INFORMATION ----------------------------------------------- LOCATION...12.2N 100.7W ABOUT 390 MI...630 KM S OF ZIHUATANEJO MEXICO MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H PRESENT MOVEMENT...NW OR 310 DEGREES AT 7 MPH...11 KM/H MINIMUM CENTRAL PRESSURE...1006 MB...29.71 INCHES WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY: None. SUMMARY OF WATCHES AND WARNINGS IN EFFECT: A Tropical Storm Watch is in effect for... * Tecpan De Galeana to Manzanillo A Tropical Storm Watch means that tropical storm conditions are possible within the watch area, generally within 48 hours. For storm information specific to your area, please monitor products issued by your national meteorological service. DISCUSSION AND OUTLOOK ---------------------- At 1200 AM CST (0600 UTC), the disturbance was centered near latitude 12.2 North, longitude 100.7 West. The system is moving toward the northwest near 7 mph (11 km/h), and this general motion is expected to continue for the next couple of days. A turn toward the west-northwest is forecast by Sunday. Maximum sustained winds are near 35 mph (55 km/h) with higher gusts. Strengthening is expected during the next couple of days. The system is forecast to become a tropical storm later today and continue strengthening on Saturday as it moves parallel to the coast of southwestern Mexico. * Formation chance through 48 hours...high...90 percent. * Formation chance through 7 days...high...90 percent. The estimated minimum central pressure is 1006 mb (29.71 inches). HAZARDS AFFECTING LAND ---------------------- Key messages for Potential Tropical Cyclone Four-E can be found in the Tropical Cyclone Discussion under AWIPS header MIATCDEP4 and WMO header WTPZ44 KNHC. RAINFALL: Rainfall totals of 2 to 4 inches, with localized amounts up to 6 inches, are possible across portions of the Mexican states of Guerrero, Michoacan, and Colima through this weekend. This rainfall may lead to areas of flooding and mudslides. For a complete depiction of forecast rainfall associated with Potential Tropical Cyclone Four-E, please see the National Weather Service Storm Total Rainfall Graphic available at hurricanes.gov/graphics_ep4.shtml?rainqpf WIND: Tropical storm conditions are possible within the watch area on Saturday. SURF: Swells generated by Potential Tropical Cyclone Four-E will affect portions of the coast of southwestern Mexico during the next few days. These swells are likely to cause life-threatening surf and rip current conditions. Please consult products from your local weather office. NEXT ADVISORY ------------- Next complete advisory at 300 AM CST. $$ Forecaster Beven

...DISTURBANCE GRADUALLY BECOMING BETTER ORGANIZED... ...TROPICAL STORM WATCH IN EFFECT FOR THE COAST OF SOUTHWESTERN MEXICO... As of 12:00 AM CST Fri Jun 13 the center of Four-E was located near 12.2, -100.7 with movement NW at 7 mph. The minimum central pressure was 1006 mb with maximum sustained winds of about 35 mph.

000
ABPZ20 KNHC 130518
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 PM PDT Thu Jun 12 2025

For the eastern and central North Pacific east of 180 longitude:

Active Systems:
The National Hurricane Center is issuing advisories on Potential
Tropical Cyclone Four-E, located in the eastern Pacific basin off
the coast of southwestern Mexico.
* Formation chance through 48 hours...high...90 percent.
* Formation chance through 7 days...high...90 percent.

Offshore of Central America and Southern Mexico:
An area of low pressure is forecast to develop late this weekend or
early next week near the coast of Central America. Environmental
conditions appear conducive for some gradual development of this
system as it moves west-northwestward near the coasts of Central
America and southern Mexico.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...30 percent.

&&
Public Advisories on Potential Tropical Cyclone Four-E are issued
under WMO header WTPZ34 KNHC and under AWIPS header MIATCPEP4.
Forecast/Advisories on Potential Tropical Cyclone Four-E are issued
under WMO header WTPZ24 KNHC and under AWIPS header MIATCMEP4.

$$
Forecaster Roberts

5-Day Uncertainty Track last updated Fri, 13 Jun 2025 02:37:07 GMT


Wind Speed Probabilities last updated Fri, 13 Jun 2025 03:21:36 GMT

5-Day Uncertainty Track last updated Fri, 13 Jun 2025 02:37:07 GMT


Wind Speed Probabilities last updated Fri, 13 Jun 2025 02:37:07 GMT

5-Day Uncertainty Track last updated Fri, 13 Jun 2025 02:37:07 GMT


Wind Speed Probabilities last updated Fri, 13 Jun 2025 02:37:07 GMT

Issued at 900 PM CST Thu Jun 12 2025 000 WTPZ44 KNHC 130235 TCDEP4 Potential Tropical Cyclone Four-E Discussion Number 2 NWS National Hurricane Center Miami FL EP042025 900 PM CST Thu Jun 12 2025 Satellite images show the disturbance is still broad with little improvement in organization this evening. There is minimal convective banding, and most of the thunderstorm activity is displaced well away from the cloud system center. The broad low remains a 30-kt disturbance for this advisory. The initial motion is estimated to be northwestward at 6 kt, though it is uncertain due to the lack of a well-defined center. The near-term motion could be erratic and slightly more northward overnight while the disturbance organizes and forms a center. But, the track guidance agrees that as the system organizes and deepens, it will resume a northwestward motion and move parallel to the coast of southwestern Mexico. Little change is shown in the updated NHC forecast, which remains near the simple and corrected consensus aids. However, larger changes could be required in future issuances depending on where and when a center eventually forms. The broad structure does not suggest strengthening will occur quickly in the near term. Once the system consolidates, the warm sea surface temperatures and moist environment appear generally favorable for intensification. Although the regional models show the system reaching hurricane status, moderate (15-20 kt) easterly shear shown by the global models for the next several days could make it difficult for that much strengthening to occur. For now, the NHC intensity forecast shows the system peaking as a strong tropical storm, in line with the simple intensity consensus. Cooler waters and drier mid-level air will lead to weakening during the latter half of the forecast period, and the system is forecast to dissipate by day 5. KEY MESSAGES: 1. The outer bands of Potential Tropical Cyclone Four-E may bring locally heavy rainfall to the Mexican states of Guerrero, Michoacán, and Colima through this weekend. Isolated flooding and mudslides, especially in areas of steep terrain, are possible. 2. The disturbance is forecast to be at tropical storm strength when it moves near the southwestern coast of Mexico on Saturday. Tropical storm conditions are possible over portions of that area. FORECAST POSITIONS AND MAX WINDS INIT 13/0300Z 11.9N 100.6W 30 KT 35 MPH...POTENTIAL TROP CYCLONE 12H 13/1200Z 12.9N 100.9W 35 KT 40 MPH...TROPICAL CYCLONE 24H 14/0000Z 14.1N 102.3W 45 KT 50 MPH 36H 14/1200Z 15.2N 103.9W 55 KT 65 MPH 48H 15/0000Z 16.2N 105.5W 60 KT 70 MPH 60H 15/1200Z 17.0N 107.5W 55 KT 65 MPH 72H 16/0000Z 17.4N 109.6W 45 KT 50 MPH 96H 17/0000Z 17.5N 113.5W 30 KT 35 MPH...POST-TROP/REMNT LOW 120H 18/0000Z...DISSIPATED $$ Forecaster Reinhart

Issued at 0300 UTC FRI JUN 13 2025 976 FOPZ14 KNHC 130233 PWSEP4 POTENTIAL TROPICAL CYCLONE FOUR-E WIND SPEED PROBABILITIES NUMBER 2 NWS NATIONAL HURRICANE CENTER MIAMI FL EP042025 0300 UTC FRI JUN 13 2025 AT 0300Z THE CENTER OF POTENTIAL TROPICAL CYCLONE FOUR-E WAS LOCATED NEAR LATITUDE 11.9 NORTH...LONGITUDE 100.6 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 30 KTS...35 MPH...55 KM/H. Z INDICATES COORDINATED UNIVERSAL TIME (GREENWICH) PACIFIC DAYLIGHT TIME (PDT)...SUBTRACT 7 HOURS FROM Z TIME HAWAIIAN STANDARD TIME (HST)...SUBTRACT 10 HOURS FROM Z TIME WIND SPEED PROBABILITY TABLE FOR SPECIFIC LOCATIONS CHANCES OF SUSTAINED (1-MINUTE AVERAGE) WIND SPEEDS OF AT LEAST ...34 KT (39 MPH... 63 KM/H)... ...50 KT (58 MPH... 93 KM/H)... ...64 KT (74 MPH...119 KM/H)... FOR LOCATIONS AND TIME PERIODS DURING THE NEXT 5 DAYS PROBABILITIES FOR LOCATIONS ARE GIVEN AS OP(CP) WHERE OP IS THE PROBABILITY OF THE EVENT BEGINNING DURING AN INDIVIDUAL TIME PERIOD (ONSET PROBABILITY) (CP) IS THE PROBABILITY OF THE EVENT OCCURRING BETWEEN 00Z FRI AND THE FORECAST HOUR (CUMULATIVE PROBABILITY) PROBABILITIES ARE GIVEN IN PERCENT X INDICATES PROBABILITIES LESS THAN 1 PERCENT PROBABILITIES FOR 34 KT AND 50 KT ARE SHOWN AT A GIVEN LOCATION WHEN THE 5-DAY CUMULATIVE PROBABILITY IS AT LEAST 3 PERCENT. PROBABILITIES FOR 34...50...64 KT SHOWN WHEN THE 5-DAY 64-KT CUMULATIVE PROBABILITY IS AT LEAST 1 PERCENT. - - - - WIND SPEED PROBABILITIES FOR SELECTED LOCATIONS - - - - FROM FROM FROM FROM FROM FROM FROM TIME 00Z FRI 12Z FRI 00Z SAT 12Z SAT 00Z SUN 00Z MON 00Z TUE PERIODS TO TO TO TO TO TO TO 12Z FRI 00Z SAT 12Z SAT 00Z SUN 00Z MON 00Z TUE 00Z WED FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT ISLAS MARIAS 34 X X( X) X( X) 1( 1) 2( 3) X( 3) X( 3) 15N 105W 34 X 2( 2) 29(31) 20(51) 1(52) X(52) X(52) 15N 105W 50 X X( X) 4( 4) 8(12) 1(13) X(13) X(13) 15N 105W 64 X X( X) X( X) 3( 3) X( 3) X( 3) X( 3) MANZANILLO 34 X X( X) 2( 2) 4( 6) 2( 8) X( 8) X( 8) L CARDENAS 34 X 1( 1) 3( 4) 2( 6) 1( 7) X( 7) X( 7) ZIHUATANEJO 34 X 1( 1) 2( 3) 2( 5) X( 5) X( 5) X( 5) 15N 100W 34 1 2( 3) 2( 5) 1( 6) X( 6) X( 6) X( 6) ACAPULCO 34 X 1( 1) 1( 2) 1( 3) X( 3) X( 3) X( 3) 15N 110W 34 X X( X) X( X) 1( 1) 5( 6) X( 6) X( 6) 20N 110W 34 X X( X) X( X) X( X) 7( 7) 1( 8) X( 8) ISLA SOCORRO 34 X X( X) X( X) X( X) 13(13) 9(22) X(22) ISLA SOCORRO 50 X X( X) X( X) X( X) 1( 1) 2( 3) X( 3) ISLA CLARION 34 X X( X) X( X) X( X) X( X) 6( 6) X( 6) $$ FORECASTER REINHART